A numerical investigation of the effects of model parameterization on the delineation of source protection zones under uncertainty.

Source protection zone delineation has evolved over the past decades from fixed radius or analytical and numerical methods which do not consider uncertainty, to more complex stochastic numerical approaches. In this paper we explore options for delineating a source protection zone, while considering the inherent uncertainty involved in characterizing hydraulic conductivity. We consider a representative pumping well in an unconfined alluvial aquifer under steady-state flow conditions, with the hydraulic conductivity distribution inferred from borehole lithology data in the West Melton area near Christchurch, New Zealand.

Reducing Uncertainty of Groundwater Redox Condition Predictions at National Scale, for Decision Making and Policy.

Understanding hydrogeochemical heterogeneity, associated with natural nitrate attenuation, is an integral part of implementing integrated land and water management on a regional or national scale. Redox conditions are a key indicator of naturally occurring denitrification in the groundwater environment, and often used to inform spatial planning and targeted regulation. This work describes the development of a statistical redox condition model for the groundwater environment at a national scale, using spatially variable physiochemical descriptors as predictors.

The dose-response relationship in physical activity interventions: Does greater duration, number of sessions, and contact time enhance behavior change?

Objectives: We tested whether an intervention's dosage influences health behavior change. Intervention dosage was indexed by the duration of the intervention, the number of sessions, and total contact time in treatment arms of trials to promote physical activity.

Method: The research comprised two studies.

Neutralizing antibody correlate of protection against severe-critical COVID-19 in the ENSEMBLE single-dose Ad26.COV2.S vaccine efficacy trial.

Assessment of immune correlates of severe COVID-19 has been hampered by the low numbers of severe cases in COVID-19 vaccine efficacy (VE) trials. We assess neutralizing and binding antibody levels at 4 weeks post-Ad26.COV2.